Casio CZ-101

images via this auction

Korg Mono/Poly MP-4

images via this auction

Anyone know more about the overlay pictured below? What does the text on the top of it say?

Update via Dan: "if i recall correctly, at the top are a few tutorials on how to design different sounds. i think i found a scanned copy of this at synthesized dreams and nightmares or zen monopoly."

Update via plug it in, in the comments: "It say: Korg Mono/Poly Sound Chart, followed by 'presets' for BRASS, SYNC SWEEP, KING GONG, STEEL DRUMS, SYNTHE GUITAR and BOWED VIOLIN"

Stamba's Live Act @ Deviant Machine (BT59-Bordeaux-FRANCE)

You can find more images via Stamba on the forum.

"Here is the recording of my live act: [link1] and [link2]. About 45min and 192kbps

Gears used :
Roland TB-303
Roland TR-505
Clavia Nord Modular
Elektron Machine Drum
MFB Synth Lite II
MFB 503
MAM MAP1
AKAI MPC500
BOSS SE-50
X-FADE LVP110
Pioneer DJM-400
Mackie 1604VLZ
http://www.stamba.fr"

YAMAHA CS-10

YouTube via elfferichfour
"Can't live without him ; my YAMAHA CS-10. Best bass sounds I have ever heard. Never let me down. listen( download for free) to 5 albums ( only analog synthesizers) at www.wmrecordings.com."

PT-20 by S-CAT

YouTube via PHONICPOTION. "CIRCUIT BENT CASIO PT-20 WITH 12 MODIFICATIONS"

TYU-40 by S-CAT

"CIRCUIT BENY YAMAHA TYU-40 WITH 2 SWITCHABLE MODIFICATIONS"

BTW, for coverage of this year's NYC Circuit Bending Festival, NYC Bent Fest 2008, check out GetLoFi

Alesis Ion easy synth-ing 3: some osc sounds

YouTube via se7ense7
"I tried to make a decent video with some good sounding clean osc sounds of the Alesis Ion synthesizer. The Windows Movie maker f*cked up the sounds in the louder parts (some wind-like sound has sneaked in for no reason). But it's still quite decent.

People always ask how the sawtooth sounds, in relation to other synths. Now you can compare for yourself.

Feel free to add comments, requests, ...

I'm not the synth god, so I do not pretend to know it all.

Pz
ARD"

Yamaha Design Exhibition 2008

Yamaha Key designs by Milano Salone 2008

click here for more.

via Synthtopia

Notebook Keyboard

classic cs60

via rafkey on VSE: "Here is a demo of my beloved Yamaha CS60"

EML-101 Multimode VCF Schematic

via Aaron on the sdiy list:
"One project idea that I tossed out to my students, which one student is trying to get work, is to use the idea of an NPN differential amp driving a "differential integrator" to build a 1-pole LPF, which you could then do four times to get a usual 4-pole LPF.

I got the idea from the EML-101 filter schematic [mirror], as expertly redrawn by Marjan Urekar:

The EML-101 is a state variable filter, and said diff amp/diff integrator configurations form the variable gain integrators.

My thought was that we could take the output of such an integrator, and feed it into the opposite input terminal of the diff pair, and that feedback should form a 1-pole LPF, as follows:

The NPN pair driving the differential integrator forms a variable gain integrator with transfer function A/RCs, where A is the voltage gain of the diff pair and R and C are the resistor values used in the integrator. Let's denote wo = A/RC. Now imagine we take the output of this integrator and feed it back into the input with a minus sign. You get something like this:

Y(s) = (wo/s) [X(s) - Y(s)]

Y(s)[1 + wo/s] = (wo/s) X(s)

Y(s)/X(s) = (wo/s) / (1+wo/s) = wo/(s+wo)

Which is the transfer function of a single-pole LPF with cutoff wo with unity gain at DC. (This is the same idea as a usual OTA-C filter 1-pole LPF).

Three questions:

1) I sent my student, Justin, this sketch to get him started, where I just blindly ganked the resistor and cap values from the EML circuit.

Anyway, I just realized I drew that wrong - the EML integrating stage is _inverting_, so we should actually either:

A) Swap the inputs on the differential integrator, to make a noninverting stage, or

B) Take the feedback to the left NPN instead of the right NPN

Does (A) or (B) sound like the safer option?

2) Given the way the "differential integrator" is going to load the differential amp, should I even be thinking of this as a differential amp followed by a differential integrator? Or are they interacting so much such thinking breaks down?

3) Does this whole crazy idea of mine sound like a decent idea at all or is it doomed to insanity?

- Aaron

P.S. This got me wondering if there's an "integrating version" of the standard 3-op-amp instrumentation amplifier? A differential integrator with high input impedance, but something more elegant than just slapping noninverting op amp buffers at the inputs to the above differential integrator?

http://en.wikipedia.org/wiki/Image:Opampinstrumentation.svg"

Switched-On-Rock

flickr by mpeake

full size

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